CN100338664C - Calibration method for improving stability of write control signal during writing - Google Patents
Calibration method for improving stability of write control signal during writing Download PDFInfo
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- CN100338664C CN100338664C CNB2004100957476A CN200410095747A CN100338664C CN 100338664 C CN100338664 C CN 100338664C CN B2004100957476 A CNB2004100957476 A CN B2004100957476A CN 200410095747 A CN200410095747 A CN 200410095747A CN 100338664 C CN100338664 C CN 100338664C
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- G—PHYSICS
- G11—INFORMATION STORAGE
- G11B—INFORMATION STORAGE BASED ON RELATIVE MOVEMENT BETWEEN RECORD CARRIER AND TRANSDUCER
- G11B7/00—Recording or reproducing by optical means, e.g. recording using a thermal beam of optical radiation by modifying optical properties or the physical structure, reproducing using an optical beam at lower power by sensing optical properties; Record carriers therefor
- G11B7/08—Disposition or mounting of heads or light sources relatively to record carriers
- G11B7/09—Disposition or mounting of heads or light sources relatively to record carriers with provision for moving the light beam or focus plane for the purpose of maintaining alignment of the light beam relative to the record carrier during transducing operation, e.g. to compensate for surface irregularities of the latter or for track following
- G11B7/0941—Methods and circuits for servo gain or phase compensation during operation
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- G—PHYSICS
- G11—INFORMATION STORAGE
- G11B—INFORMATION STORAGE BASED ON RELATIVE MOVEMENT BETWEEN RECORD CARRIER AND TRANSDUCER
- G11B20/00—Signal processing not specific to the method of recording or reproducing; Circuits therefor
- G11B20/10—Digital recording or reproducing
- G11B20/18—Error detection or correction; Testing, e.g. of drop-outs
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- G—PHYSICS
- G11—INFORMATION STORAGE
- G11B—INFORMATION STORAGE BASED ON RELATIVE MOVEMENT BETWEEN RECORD CARRIER AND TRANSDUCER
- G11B7/00—Recording or reproducing by optical means, e.g. recording using a thermal beam of optical radiation by modifying optical properties or the physical structure, reproducing using an optical beam at lower power by sensing optical properties; Record carriers therefor
- G11B7/08—Disposition or mounting of heads or light sources relatively to record carriers
- G11B7/09—Disposition or mounting of heads or light sources relatively to record carriers with provision for moving the light beam or focus plane for the purpose of maintaining alignment of the light beam relative to the record carrier during transducing operation, e.g. to compensate for surface irregularities of the latter or for track following
- G11B7/0948—Disposition or mounting of heads or light sources relatively to record carriers with provision for moving the light beam or focus plane for the purpose of maintaining alignment of the light beam relative to the record carrier during transducing operation, e.g. to compensate for surface irregularities of the latter or for track following specially adapted for detection and avoidance or compensation of imperfections on the carrier, e.g. dust, scratches, dropouts
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- G—PHYSICS
- G11—INFORMATION STORAGE
- G11B—INFORMATION STORAGE BASED ON RELATIVE MOVEMENT BETWEEN RECORD CARRIER AND TRANSDUCER
- G11B7/00—Recording or reproducing by optical means, e.g. recording using a thermal beam of optical radiation by modifying optical properties or the physical structure, reproducing using an optical beam at lower power by sensing optical properties; Record carriers therefor
- G11B7/12—Heads, e.g. forming of the optical beam spot or modulation of the optical beam
- G11B7/125—Optical beam sources therefor, e.g. laser control circuitry specially adapted for optical storage devices; Modulators, e.g. means for controlling the size or intensity of optical spots or optical traces
- G11B7/126—Circuits, methods or arrangements for laser control or stabilisation
- G11B7/1263—Power control during transducing, e.g. by monitoring
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- G—PHYSICS
- G11—INFORMATION STORAGE
- G11B—INFORMATION STORAGE BASED ON RELATIVE MOVEMENT BETWEEN RECORD CARRIER AND TRANSDUCER
- G11B7/00—Recording or reproducing by optical means, e.g. recording using a thermal beam of optical radiation by modifying optical properties or the physical structure, reproducing using an optical beam at lower power by sensing optical properties; Record carriers therefor
- G11B7/12—Heads, e.g. forming of the optical beam spot or modulation of the optical beam
- G11B7/125—Optical beam sources therefor, e.g. laser control circuitry specially adapted for optical storage devices; Modulators, e.g. means for controlling the size or intensity of optical spots or optical traces
- G11B7/126—Circuits, methods or arrangements for laser control or stabilisation
- G11B7/1267—Power calibration
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- G—PHYSICS
- G11—INFORMATION STORAGE
- G11B—INFORMATION STORAGE BASED ON RELATIVE MOVEMENT BETWEEN RECORD CARRIER AND TRANSDUCER
- G11B7/00—Recording or reproducing by optical means, e.g. recording using a thermal beam of optical radiation by modifying optical properties or the physical structure, reproducing using an optical beam at lower power by sensing optical properties; Record carriers therefor
- G11B7/002—Recording, reproducing or erasing systems characterised by the shape or form of the carrier
- G11B7/0037—Recording, reproducing or erasing systems characterised by the shape or form of the carrier with discs
- G11B7/00375—Recording, reproducing or erasing systems characterised by the shape or form of the carrier with discs arrangements for detection of physical defects, e.g. of recording layer
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- G—PHYSICS
- G11—INFORMATION STORAGE
- G11B—INFORMATION STORAGE BASED ON RELATIVE MOVEMENT BETWEEN RECORD CARRIER AND TRANSDUCER
- G11B7/00—Recording or reproducing by optical means, e.g. recording using a thermal beam of optical radiation by modifying optical properties or the physical structure, reproducing using an optical beam at lower power by sensing optical properties; Record carriers therefor
- G11B7/004—Recording, reproducing or erasing methods; Read, write or erase circuits therefor
- G11B7/0045—Recording
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- Physics & Mathematics (AREA)
- Optics & Photonics (AREA)
- Engineering & Computer Science (AREA)
- Signal Processing (AREA)
- Optical Recording Or Reproduction (AREA)
- Optical Head (AREA)
- Moving Of The Head For Recording And Reproducing By Optical Means (AREA)
- Control Of Electric Motors In General (AREA)
Abstract
A calibration method for improving stability of write control signal during writing can be applied in a CD recorder. The CD recorder has a pickup device having a laser diode, and a write control device for outputting a write control signal. A first relationship curve showing the relationship between the write control signal and a light-emitting power generated by the laser diode is obtained by switching the pickup device into a de-focus state and switching the write control device into a close-loop mode. A second relationship curve showing the relationship between a gain of the write control device and the write control signal is obtained by switching the write control device into a long-term open mode. When a specific light-emitting power is adapted to write, a specific write control signal and a specific gain corresponding to the specific light-emitting power is obtained according to the first and second relationship curves.
Description
Technical field
The present invention relates to a kind of calibration steps, especially relate to a kind of calibration steps of stability of the write control signal when improving burning.
Background technology
Please refer to Fig. 1, it shows the calcspar of conventional optical disc cd-rom recorder.Optical disk recording device mainly has a read control device 10, an into control device 20 and a read-write head device 30.In the time will carrying out data read, read control device 10 produces one and reads controlling signal VRDC, and exports the drive IC 304 of read-write head device 30 to.Drive IC 304 will produce a current i of flowing through laser diode (Laser Diode) 301 according to reading controlling signal VRDC
D, come disc 40 is carried out read operation to produce laser beam.And write fashionablely when carrying out data, into control device 20 will produce a write control signal VWDC, and export the drive IC 304 of read-write head device 30 to.Drive IC 304 will produce current i according to write control signal VWDC
D, come disc 40 is carried out write operation to produce laser beam.
On the other hand, 302 laser beams according to 301 sensings of laser diode of the monitoring diode of read-write head device 30 (Monitor Diode) produce a current i
MCurrent i
MAfter the processing via computing the 3rd amplifier 303, will produce a back coupling controlling signal FPDO.Back coupling controlling signal FPDO will feedback to the input end of read control device 10 with into control device 20, the luminous power that the laser diode 301 when carrying out read/write with control produces.
Please refer to " into control device of light storage facilities and method " in No. 92100819, the Taiwan number of patent application of on January 15th, 2003 application, it has disclosed into control device 20 and has had three kinds of mode of operations, comprise short time open circuit mode (Short-term open mode), long-time open circuit mode (Long-term open mode) and closed loop pattern (Close-loop mode), respectively as Fig. 2, Fig. 3 and shown in Figure 4.In short time open circuit mode shown in Figure 2, write control signal VWDC initialization by the virtual earth effect (Virtual ground) of first amplifier 201, and make write control signal VWDC become zero potential.In long-time open circuit mode shown in Figure 3, voltage level is that the analog signal DAC2 of V1 inputs to and puts in the second largest device 203.The yield value G of second amplifier 203 is V2/V1, and second amplifier 203 and output-voltage levels are output signal to the first amplifier 201 of V2, make first amplifier, 201 output-voltage levels become the write control signal VWDC of V2.Analog signal DAC2 is the signal that influences the level size of write control signal VWDC, and it can be by obtaining after digital value of a digital analog converter conversion.This digital value can be selected from one of a plurality of digital values that are stored in the internal memory, and different numerical value will determine the size of different write control signal VWDC.In this long-time open circuit mode, write control signal VWDC can be charged to the voltage level V2 that can carry out burning to CD 40 apace.And in the pattern of the closed loop of Fig. 4, back coupling controlling signal FPDO inputs to after the into control device 20, elder generation is taken a sample by sampling keeping unit S/H and keeps operation, and amplify after G12 times, input to the negative input end of first amplifier 201 via resistance R i2, voltage level is the positive input terminal that the analog signal DAC2 of V1 then directly is fed into first amplifier 201.First amplifier 201 and output-voltage levels are the write control signal VWDC of V2 ', and stride across parallel resistor Rf2 and resistance C2 and feedback to the negative input end of first amplifier 201.In this closed loop pattern, write control signal VWDC in order to control read-write head device 30, with burning data to CD 40.
Significantly, under perfect condition, above-mentioned V2 ' should equate with the V2 voltage level.Please refer to Fig. 5 A, it shows when V2 ' equates with V2, the signal waveform figure of a period controlling signal WLDON and write control signal VWDC, and wherein period controlling signal WLDON is in order to control into control device 20.When the period, controlling signal WLDON switched to high level, into control device 20 will switch to the closed loop pattern to carry out the burning operation.Therefore, in time section T 1, period controlling signal WLDON is a low level, and into control device 20 enters long-time open circuit mode, and the level of write control signal VWDC is V2.In time section T 2, the period, controlling signal WLDON transferred high level to, and into control device 20 enters the closed loop pattern, and the level of write control signal VWDC is V2 '.So, earlier by long-time open circuit mode, make write control signal VWDC charge to the voltage level V2 that can carry out burning apace to CD 40, then, mat closed loop pattern again, make write control signal VWDC be maintained at the voltage level V2 ' (V2 ' equals V2 under the perfect condition) that can carry out burning, can avoid CD-ROM drive when carrying out write operation, to produce mistake CD 40.
Yet if the yield value G of second amplifier 203 design is bad, or because of environmental factor or Temperature Influence change the yield value G of second amplifier 203, the value of V2 ' will can not equate with the value of V2.Please refer to Fig. 5 B, it shows when V2 ' and V2 are unequal, the signal waveform figure of period controlling signal WLDON and write control signal VWDC.It is unequal with V2 to work as V2 ', and when into control device 20 switches to the closed loop pattern of time section T 2 by the long-time open circuit mode of time section T 1, the situation that write control signal VWDC will have instantaneous spread of voltage produces, and may allow CD-ROM drive produce mistake when carrying out write operation.
In addition, tradition is used in the hope of the method for the yield value G of second amplifier 203 as follows.Generally before carrying out burning, carry out OPC (Optimum Power Control) calibration prior to the test section (test area) of disc, the OPC calibration is that laser diode carries out burning in the test section with different luminous powers.In this OPC calibration process, can be in the hope of the luminous power of suitable burning, and according to this luminous power push away the gain theory value of second amplifier 203.Then, with the yield value G of this fixing gain theory value as second amplifier 203.But, for CAV (Constant Angle Velocity) CD-ROM drive, when the burning multiple not simultaneously, then must set different luminous powers, that is set different yield value G to obtain the voltage level V2 of different write control signal VWDC.Significantly, traditional practice also can't reach the function that changes yield value G along with different burning multiples, so this method also has the spread of voltage of write control signal VWDC, and the situation of the error in data that writes is taken place.
Summary of the invention
In view of this, the present invention proposes a kind of calibration steps of stability of the write control signal when improving burning, can improve the situation of above-mentioned write control signal VWDC spread of voltage when switching to the closed loop pattern effectively, and then the data of avoiding writing to disc produce mistake by long-time open circuit mode.
According to purpose of the present invention, a kind of being applied in the optical disk recording device proposed, the calibration steps of the stability of the write control signal when improving burning.Optical disk recording device has a pick-up device and an into control device, and into control device is in order to export a write control signal.Calibration steps in the preferred embodiment of the present invention obtains a yield value in the into control device, and this yield value is in order to the control write control signal, and this write control signal control pick-up device carries out write operation to disc.The method of preferred embodiment of the present invention comprises the following step.At first, switch pick-up device and transfer a non-focusing state to.Then, switching into control device is a closed loop pattern, and obtains first relation curve of the luminous power value of write control signal and laser diode generation.Then, into control device is switched to a long-time open circuit mode, and obtain second relation curve of an Amplifier Gain value and write control signal in the into control device.So, finish after the calibration, carry out burning when this pick-up device will make laser diode produce specific luminous power, this optical disk recording device can be according to first relation curve, and obtain corresponding to the specific write control signal under this specific luminous power.Then, again according to second relation curve, obtain certain gain value that should specific write control signal, make the write control signal that into control device is exported under this long-time open circuit mode, equal in fact under the pattern of closed loop, into control device is in the specific write control signal of output.
Can become apparent for penetrating above-mentioned purpose of the present invention, feature and advantage, a preferred embodiment cited below particularly, and be described with reference to the accompanying drawings as follows.
Description of drawings
Fig. 1 shows the calcspar of conventional optical disc cd-rom recorder.
Fig. 2 shows short time open circuit mode circuit diagram.
Fig. 3 shows long-time open circuit mode circuit diagram.
Fig. 4 shows closed loop mode circuit figure.
Fig. 5 A and 5B show the signal waveform figure of period controlling signal and write control signal.
The process flow diagram of calibration (calibration) method of the stability of the write control signal when Fig. 6 shows and improves burning according to preferred embodiment of the present invention a kind of.
Fig. 7 shows the relation curve of write control signal and luminous power desired value.
Fig. 8 shows the relation curve of the relative gain value of the write control signal and second amplifier.
The drawing reference numeral explanation
10: read control device
20: into control device
30: pick-up device
201: the first amplifiers
203: the second amplifiers
301: laser diode
302: monitoring diode
303: the three amplifiers
304: drive IC
Embodiment
Please refer to Fig. 6, the process flow diagram of calibration (calibration) method of the stability of the write control signal when it shows and improves burning according to preferred embodiment of the present invention a kind of.The present invention operates by online (On-line), and the optical read head 30 that directly changes in the CD-ROM drive is calibrated with the state of into control device 20.At first, enter step 602, make optical read head transfer non-focusing state (De-focus) to earlier, for example make the position of optical read head move to below, make optical read head can not have influence on the state of disc, that is data really can not write in the disc.Then, enter step 604, into control device 20 is switched to the closed loop pattern, and try to achieve the magnitude of voltage of write control signal VWDC and the relation curve of the luminous power desired value that laser diode 301 produces.Then, enter step 606, into control device 20 is switched to long-time open circuit mode, and try to achieve the relation curve of the magnitude of voltage of the yield value G of second amplifier 203 and write control signal VWDC.
Please refer to Fig. 7, it shows an example of the relation curve of the magnitude of voltage of write control signal VWDC in the step 604 and the luminous power desired value that laser diode 301 produces.This relation curve ask method as follows: at first, configuring several luminous power desired values, for example is 100mW, 200mW, 300mW and 400mW.Then, the back coupling controlling signal FPDO that corresponds to these luminous power desired values is feedback to the writing controller 20 of closed loop pattern shown in Figure 4, and measure the magnitude of voltage of the write control signal VWDC that writing controller 20 exported, for example be A1, A2, A3 and A4.Wherein, the magnitude of voltage of write control signal VWDC can be the voltage level of write control signal VWDC is back via analog-to-digital converter (ADC) conversion and digital value that get.
Please refer to Fig. 8, it shows an example of magnitude of voltage with the relation curve of the corresponding yield value G of second amplifier 203 of write control signal VWDC in the step 606.This relation curve ask method as follows: the magnitude of voltage of the write control signal VWDC that gets according to measurement, for example be A1, A2, A3 and A4, voltage level in analog signal DAC2 is a fixed value, for example be V1, condition under, obtain Fig. 3 shown in the writing controller 20 of long-time open circuit mode in the corresponding yield value of second amplifier 203, for example be G1, G2, G3 and G4.
So, finish after the calibration, if will make laser diode produce specific luminous power carries out burning, can try to achieve the magnitude of voltage of the write control signal VWDC under this pairing closed loop of specific luminous power pattern apace earlier according to relation curve shown in Figure 7.Then, again according to relation curve shown in Figure 8, try to achieve the yield value G under the pairing long-time open circuit mode of magnitude of voltage of this write control signal VWDC.When for example being 200mW by the specific luminous power that OPC obtained, the magnitude of voltage that can utilize the relation curve correspondence of Fig. 7 to go out write control signal VWDC is A2.Utilize this VWDC magnitude of voltage A2 subsequently again in the relation curve of Fig. 8, correspondence goes out second amplifier, the 203 yield value G2 under the long-time open circuit mode.So after utilizing the corresponding yield value G2 that goes out of institute to adjust the yield value of second amplifier 203 when burning, just can in the burning process, keep stablizing of VWDC magnitude of voltage.In addition, for the CAV CD-ROM drive, can set up the relation curve (for example setting up Fig. 7,8 relation curve) of the voltage level V2 of different write control signal VWDC at different yield value G, and go out required yield value G according to required recording power correspondence, so just reduce the situation that writes error in data.In addition, the enforcement point of the method for preferred embodiment of the present invention, can be in the CD-ROM drive preceding enforcement of dispatching from the factory, also visual practical situation is implemented before each burning data, those skilled in the art can be changed according to practical application, right all modification or changes under the prerequisite that does not break away from preferred embodiment spirit of the present invention all should be contained in the claim of the present invention.
The calibration steps that the above embodiment of the present invention is disclosed, can realize the advantage of accurate ride gain value G, make when writing controller 20 switches to the closed loop pattern by long-time open circuit mode, write control signal VWDC can be as shown in Fig. 5 A, can maintain fixing voltage level, make the data that write to disc can wrongly not produce.And, for the CAV CD-ROM drive, also can apace not simultaneously, set different yield value G by method of the present invention to obtain the voltage level V2 of different write control signal VWDC in the burning multiple.
In sum; though the present invention discloses as above with a preferred embodiment; right its is not in order to limit the present invention; those skilled in the art can be used for a variety of modifications and variations under the premise without departing from the spirit and scope of the present invention, so protection scope of the present invention is as the criterion with claim of the present invention.
Claims (13)
1. the calibration steps of the stability of the write control signal when improving burning, be used for an optical disk recording device, this optical disk recording device has a pick-up device and an into control device, this into control device is in order to export a write control signal, this calibration steps obtains a yield value in this into control device, this yield value is in order to control this write control signal, and this write control signal is controlled this pick-up device one disc is carried out write operation, and this calibration steps comprises:
Switching this pick-up device is a non-focusing state;
Switching this into control device is a closed loop pattern, and obtains one first relation curve of this write control signal and laser diode generation luminous power value;
This into control device is switched to a long-time open circuit mode, and obtain one second relation curve of this yield value and this write control signal;
Wherein, when this pick-up device will use a specific luminous power to carry out burning, this optical disk recording device was carried out the following step:
Obtain corresponding to a specific write control signal under this specific luminous power according to this first relation curve;
Obtain a certain gain value that should specific write control signal according to this second relation curve, make this write control signal that this into control device is exported under this long-time open circuit mode, equal under this closed loop pattern this specific write control signal of this into control device output.
2. calibration steps as claimed in claim 1, wherein this calibration steps is calibrated by the mode of an on-line operation.
3. calibration steps as claimed in claim 2, the step of wherein switching this pick-up device and be a non-focusing state comprises:
The position of one optical read head is moved to below, make this optical read head can not influence data and write in the disc, wherein this optical read head is arranged in this pick-up device.
4. calibration steps as claimed in claim 3, wherein in this closed loop pattern, the step of trying to achieve this first relation curve comprises:
A. set a plurality of luminous power desired values;
B. produce a plurality of back coupling controlling signal of corresponding described luminous power desired value, described back coupling controlling signal is feedback to this closed loop pattern in this into control device;
C. measure a plurality of write control signal desired values that correspond to described back coupling controlling signal; And
D. obtain this first relation curve according to described luminous power desired value and said write controlling signal desired value.
5. calibration steps as claimed in claim 4, wherein in this long-time open circuit mode, the step of trying to achieve this second relation curve comprises:
E. input in one second amplifier according to said write controlling signal desired value, and in another input end of this second amplifier be the voltage level of an analog signal under the fixing condition, obtain corresponding a plurality of gain target values of one first amplifier in this writing controller of this long-time open circuit mode; And
F. according to said write controlling signal desired value and described gain target value, obtain this second relation curve.
6. calibration steps as claimed in claim 5, in this closed loop pattern, this into control device receives this back coupling controlling signal, produces this specific write control signal in order to control a laser diode in this pick-up device, and this laser diode carries out write operation to this disc.
7. calibration steps as claimed in claim 6, in this long-time open circuit mode, voltage level when this write control signal rapid charge extremely can be carried out burning to this disc, this into control device has this second amplifier, this second amplifier has this yield value, and this yield value is in order to control this write control signal.
8. calibration steps as claimed in claim 7, this method make when CD-ROM drive will carry out burning with this certain power, can learn this certain gain value by the first/the second relation curve, make this write control signal charge to this specific write control signal size.
9. calibration steps as claimed in claim 1, wherein, when this into control device is this closed loop pattern, one positive input terminal of one first amplifier in this into control device is in order to receive a voltage level, and export this write control signal by the output terminal of this first amplifier, this write control signal more inputs to a negative input end of this first amplifier via linear circuit back coupling, and it is relevant with this write control signal that this negative input end receives this back coupling controlling signal, and, under this long-time open circuit mode, this into control device has this first amplifier and one second amplifier, this second amplifier has this yield value, and this second amplifier is in order to receiving this voltage level, and this voltage level is multiplied by this yield value makes the magnitude of voltage of output signal of this second amplifier equal this write control signal.
10. calibration steps as claimed in claim 9, wherein this calibration steps is calibrated by the mode of an on-line operation.
11. calibration steps as claimed in claim 10, wherein this pick-up device of this switching is that the step of a non-focusing state comprises:
The position of one optical read head is moved to below, make this optical read head can not influence data and write in this disc, wherein this pick-up device has this optical read head, and this optical read head also has laser diode and monitoring diode.
12. calibration steps as claimed in claim 11, wherein this method makes this into control device under this closed loop mode step, and the step of trying to achieve this first relation curve comprises:
A. set a plurality of luminous power desired values;
B. will correspond to a plurality of back coupling controlling signal of described luminous power desired value, described back coupling controlling signal is feedback to this first amplifier;
C. measure a plurality of write control signal desired values that correspond to described back coupling controlling signal; And
D. obtain this first relation curve according to described luminous power desired value and said write controlling signal desired value.
13. calibration steps as claimed in claim 12, wherein this method makes this into control device under this long-time open circuit mode step, and the step of trying to achieve this second relation curve comprises:
E. according to said write controlling signal desired value, and be under the condition of a fixed voltage level in an input end of this second amplifier, obtain corresponding a plurality of target gain value of this second amplifier in this into control device under this long-time open circuit mode; And
F. according to the relation of said write controlling signal desired value and target gain value, obtain this second relation curve;
Wherein this into control device is under this long-time open circuit mode, this second amplifier has an output terminal and an input end, this input end receives this fixed voltage level, the positive input terminal of this output terminal and this first amplifier links, the output terminal of this first amplifier is connected with negative input end to export this write control signal, and this write control signal also inputs to this input end of this second amplifier via linear circuit back coupling.
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| US52071103P | 2003-11-17 | 2003-11-17 | |
| US60/520,711 | 2003-11-17 |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN1619662A CN1619662A (en) | 2005-05-25 |
| CN100338664C true CN100338664C (en) | 2007-09-19 |
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Family Applications (6)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CNB2004100957461A Active CN1293539C (en) | 2003-11-17 | 2004-11-17 | Method and apparatus for writing re-writable optical disk |
| CNB2004100957476A Active CN100338664C (en) | 2003-11-17 | 2004-11-17 | Calibration method for improving stability of write control signal during writing |
| CNB2004100957442A Active CN1305048C (en) | 2003-11-17 | 2004-11-17 | Focusing controller and method thereof for an optical disk drive |
| CNB2004100957457A Active CN1310220C (en) | 2003-11-17 | 2004-11-17 | Method and device for generating a stable power control signal |
| CNB2004100957495A Active CN1280804C (en) | 2003-11-17 | 2004-11-17 | Focusing controllter and method thereof for an optical disk drive |
| CNB2004100957480A Active CN1310229C (en) | 2003-11-17 | 2004-11-17 | Method and device for adjusting a control parameter of a servo of an optical drive |
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| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CNB2004100957461A Active CN1293539C (en) | 2003-11-17 | 2004-11-17 | Method and apparatus for writing re-writable optical disk |
Family Applications After (4)
| Application Number | Title | Priority Date | Filing Date |
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| CNB2004100957442A Active CN1305048C (en) | 2003-11-17 | 2004-11-17 | Focusing controller and method thereof for an optical disk drive |
| CNB2004100957457A Active CN1310220C (en) | 2003-11-17 | 2004-11-17 | Method and device for generating a stable power control signal |
| CNB2004100957495A Active CN1280804C (en) | 2003-11-17 | 2004-11-17 | Focusing controllter and method thereof for an optical disk drive |
| CNB2004100957480A Active CN1310229C (en) | 2003-11-17 | 2004-11-17 | Method and device for adjusting a control parameter of a servo of an optical drive |
Country Status (3)
| Country | Link |
|---|---|
| US (9) | US7286462B2 (en) |
| CN (6) | CN1293539C (en) |
| TW (6) | TWI261237B (en) |
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| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US7586822B2 (en) * | 2003-07-18 | 2009-09-08 | Mediatek Inc. | Optical drive controller providing calibrated laser diode driver |
| US7286462B2 (en) | 2003-11-17 | 2007-10-23 | Via Technologies, Inc. | Method and device for generating a stable power control signal |
| TWI261226B (en) * | 2004-01-20 | 2006-09-01 | Via Tech Inc | Apparatus and method of dynamic adjusting the detection window |
| TWI261240B (en) | 2004-08-17 | 2006-09-01 | Via Tech Inc | Method for determining data storage quality of optical disc |
| CN100394491C (en) * | 2005-06-29 | 2008-06-11 | 联发科技股份有限公司 | Optical storing device control circuit and method thereof |
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